How Baba Is You Works | GMTK Most Innovative 2019

Every December, I use my last video of the
year to celebrate the most innovative and

inventive game I played in the last 12 months.

In previous years I’ve looked at the YouTube
detective drama Her Story, the uncanny chatbot

game Event[0], the serpent simulator Snake
Pass, and the time-travelling murder mystery,

Return of the Obra Dinn.

These games have done things I’ve never
seen before, and are impressive in both their

idea and their execution.

They might not be the very best games of their
respective years, but when it comes to fresh

concepts done well, these are the games I
would recommend.

I certainly had lots of choices to pick from
for 2019, like the combat-free role playing

game Disco Elysium, the hilarious honk ‘em
up Untitled Goose Game, the sci-fi archeology

game Outer Wilds, and the other sci-fi archeology
game, Heaven’s Vault.

But this year, nothing quite beat the mind-melting
puzzle game, Baba Is You.

Now, from first glance, this game looks pretty
simple.

You hop around a grid and push blocks - making
it part of a sub genre of block-shoving puzzlers,

all inspired by the Japanese game Sokoban.

Here’s where things start getting strange,
though: in each level, the rules of the game

are written on screen as simple sentences.

Like, “Baba Is You”, which means you control
this funny white critter called Baba.

Or “Wall Is Stop”, which means you can’t
walk through walls.

“Rock Is Push” means you can shove rocks
around, and “Flag Is Win” means touching

the flag will finish the level.

And then here’s the kicker: those rules
are, themselves, blocks that can be pushed

around - allowing you to break the logic that
dictates the level at hand, and create entirely

new gameplay by rewriting the rules.

Remove the word “Stop” from “Wall Is
Stop”, for example, and now you can waltz

straight past walls.

Change “Flag Is Win” to “Rock Is Win”,
and now the rock becomes your goal.

Or push "Rock: into this sentence, and you switch
the main character of the game into a tiny

brown boulder.

Cheeky.

And thus begins a few hundred levels where
the solution is never to simply reach the

goal - but to rewrite the rules of the universe
until you’re in a world where the goal is

now reachable.

It is infinitely intelligent and endlessly
surprising.

It’s tough, but far from impossible, and
practically every level is a revalatory experience

with a satisfying aha! moment.

And if you haven’t played it yet, now’s
your time to pause the video, head to Steam

or the Switch eShop, and get the game.

I hope that you love it.

When you’re done, remember to come back,
and we’ll chat more about how the game builds

its brain-busting puzzles

Baba Is You is the brain-child of Finnish
indie developer Arvi Teikari.

He told me over email back in April that he
was inspired to make the game as part of the

2017 Nordic Game Jam.

The jam’s theme was “Not There”, and
the word “Not” made him think of logic

operators in programming languages.

Combine that with a block-pushing puzzle game
like Snakebird or Stephen’s Sausage Roll,

and this “resulted in a mental image of
a block of ice not melting in hot lava due

to the statement "Ice Is Not Melt”.

The scrappy, prototypical Baba Is You ended
up winning that Game Jam, and the reaction

was so positive that Teikari decided to take
his underbaked jam game and turn it into a

full fat release.

Two years later, and the designer had about
219 ultra clever levels for players to work through.

So how, exactly, is one of these Baba Is You
levels made?

To start, Teikari tries to think of an interesting
interaction, or set-up that could come out

of the game’s encyclopaedia of words and
rules.

“Pull”, for example, could lead to a level
where Keke needs to drag a key across a lake.

A teleporter doesn’t have to just move objects,
but could also be used to move around the

rules themselves.

And the word “Has”, could lend itself
to a level where you drop a box every-time

Keke dies, but that box immediately turns
back into Keke.

Bonkers.

Speaking at the Gamelab conference in Barcelona
this summer, Teikari said, “when I’ve

got this idea of ‘hey, that would be cool
to see in a level’, I try to figure out

what kind of level do I have to build so that
when the player is playing the level they

have to use that interaction”.

And that’s where we get to the fascinating
contradiction at the heart of Baba Is You.

Because while this is a game that offers a
seemingly infinite world of possibilities

- its puzzles are largely defined by what
you can’t do.

Because while making an open ended puzzle
game sounds great, it’s open to easy answers

- like Scribblenauts, where half of the levels
can be finished by writing in the word jetpack.

So the designer’s job is actually to lock
you in and force restrictions on you.

And in Baba Is You that’s achieved by the
words that are and aren’t on screen, the

way some sentences are pushed against walls
or locked behind fences, and the claustrophobic

grid that constricts your movements.

With these restrictions in place, the designer
can lock off easy answers - and force you

to find the clever trick at the heart of the
puzzle.

Teikari calls this process reverse engineering
- of essentially starting with the solution

and then working backwards to throw up restrictions
and make a puzzle that supports it.

As an example, take the level Baba Doesn’t
Respond.

In this level we play as Keke, and the solution
is to use two belts to redirect a moving Baba.

So how does the designer force this interaction?

Let’s start by putting a wall and a locked
door between Keke and the Flag.

If we put a rule here like “Door Is Shut
And Open”, we can just push the word “Shut”

over and then go to the flag.

But if we put a reed here, and make it so
creating that first sentence simultaneously

makes the rule “Reed Is Defeat”, we suddenly
put Keke in a pickle - opening the door also

denies access to that door.

Hm! Quite the catch!

So, the player will hopefully realise that
they need to have Keke be stood in this exact

spot when the rule is triggered - and they just
need to figure out how to move the sentence

from afar.

Answer: “Baba Is Move”.

Now the level would be way too easy if we
could just put Baba here, make “Baba Is

Move”, and then walk to the right spot and
wait for Baba to walk into the words.

So, some restrictions are added.

This single hedge block means Baba only has
a tiny run-up.

And having “Move” be in the corner makes
it impossible to, well, move, so the sentence

“Baba Is Move” has to be made on the furthest
left edge of the screen.

These two things combine to make it impossible
to make “Baba Is Move” and then walk to

that all-important spot, because Baba will
have already made the reed deadly by the time

you get there.

And thus, you must use these belts to create
a much longer path for Baba to take, Chu Chu

Rocket style, which will give you enough time
to walk across the level before he triggers

the sentence change.

Then it’s just a case of sprinkling on some
pretty decoration, and putting in some other

bits to restrict your movement or stop unintended
solutions.

Though, many of those are left in by the designer

- provided they don’t make the real solution trivial.

So as you can see, the solution to the puzzle
is actually pretty simple.

But by obfuscating the answer behind a sequence
of problems, it creates this interesting phenomenon

where Teikari is working backwards from the
solution, locking up doors behind him as he

gets to the starting conditions for the puzzle.

And then the player then moves in the opposite
direction, opening each door in turn until

they get to the solution.

And by setting the stage up in this way, the
player is actually somewhat lured towards

the solution.

Each level contains a number of tiny problems
that render something impossible - forcing

the player to find a different, more creative
way to overcome the problem.

These stumbling blocks then stack together,
creating a pathway to the level’s solution.

Here’s how that looks in a favourite stage
of mine: Tiny Pond.

In this level, the word “Win” needs to
be released from a pond.

The water is tagged as “Shut”, and Baba
is tagged as “Open”, which means you can walk

into the water to unlock it and gain access
- but this also destroys Baba.

So, we’re going to need to try something
else.

We’ve got two other words: “Key” and
“Flag”, and so we could make “Key Is

Open”, but there’s no “Push” verb,
meaning the key just sits there.

The only way to make it move is to write “Key
Is You”, but we run into the same problem:

you’re destroyed as soon as you touch the
water.

By now you should hopefully be thinking, “okay,
maybe I can be both key and Baba at the same

time, because when one dies, I can still control
the other one”.

But, sadly, there aren’t enough words to
make that sentence work.

However, the sequence of logical leaps have
got you this far and there’s only one possible

way forward now: if you make flag is key,
you’ve got two keys.

And now if you have “Key Is You”, you
can control both, sacrifice one to open a

hole in the water, and use the remaining key
to finish the stage.

It’s really clever.

The set-up for the stage walked us right into
the central problem of the level: we need

to be “Open”, but we also don’t want
to disappear when we use ourselves.

And so we’re in the perfect spot to try
and figure out the actual solution - and go

“aha!” when we get there.

If this was the first level that you played
in this game, you would be - I think -

completely stumped.

But luckily, playing Baba Is You means constantly
adding to an ever expanding knowledge base

that grows with every stage you play.

So Tiny Pond builds on the level Jelly Throne,
where you control two characters at once.

And Tiny Pond’s solution reappears in the
stage Unreachable Shores, where you sacrifice

one Keke, so the survivor can move forward.

But this sort of learning starts from the
very beginning of the game.

Baba Is You is a pretty complicated puzzler,
after all, and there’s not a single tutorial

in sight.

Instead, the game’s first crop of puzzles
all subtly and silently tell you how the game

works through their solutions.

So in Level 1, we’re stuck inside a tiny
box.

There’s only one way to get out and that’s
to break the sentence “Wall Is Stop”,

and make the wall no longer a solid object.

Then, we can make a sentence - “Flag Is
Win” - to finish the level.

That’s breaking and making sentences: the
two most fundamental concepts of the game.

Level 2 is the exact same stage as before
but now everything is wrong.

You play as a wall, the walls are made of
flags, and Baba is nowhere to be found.

This teaches players that nothing in the game
has an intrinsic value: it’s only given

purpose when part of a rule.

The game keeps this up throughout its first
few stages, with solutions that clue us in

to some fundamental concept we’ll definitely
need to know later.

Here, “Lava Is Push overrides” the rule
“Lava Is Hot”.

In this puzzle, we learn that we can create
two sentences from the same “Is” block,

by creating them in a cross.

And the game will continue to teach new concepts
and ideas throughout the adventure.

Every time a new concept is introduced - like
the operator “And” or the words “Open”

and “Shut”, we’re treated to introductory
puzzles that make these new mechanics crystal clear.

I asked Teikari how he went about making these
introductory stages, and he said “If I exhaustively

go through all the meaningful interactions
between elements, eventually I get levels

where the ‘trick’ is mostly just the basic
functionality of a specific element in itself”.

that can then be put at the beginning of the
world, to act as a tutorial for the stages

to come.

While Baba Is You is full of puzzles that
will make you feel stumped when you first

play them, and make you feel smart when you
solve them, Teikari’s real goal is to create

moments of surprise and laughter.

YOUTUBER: [Laughter].

YOUTUBER: “There’s no rule saying ‘Wall
Is Stop’. [Laughter]

I was confining myself to this stupid little
area and I didn’t need to.”

That’s certainly one way it’s done - by playing
with your expectations for how things work.

In this level, for example, most players will
assume they need to unlock the door.

But actually they need to unlock the wall.

There are also just bonkers rules that go
way beyond the basic set-up.

“Empty” allows you to control or fill
the empty space in each stage.

“Make” lets you create a trail of objects
when you move.

“More” lets you duplicate keys until they
fill every spot in the space.

And just like the original idea for the game,
“Not” allows you to flip rules on their head.

Plus, in an attempt to make sure every single
interaction is explored - a similar design

philosophy as one used by Braid developer
Jonathan Blow - Teikari has “Text” be

a word, allowing you to manipulate the rules
with other rules.

And by the time “Level” is introduced,
you’re not only moving the entire screen

around - but breaking out the stage and bouncing
around the map screen in a mind-melting meta

exploration of the game’s fundamental logic.

There were more ideas that didn’t make the
cut, of course.

Teikari told me that “Stick”, which would
make objects clump together, was removed because

it created nightmare programming problems.

And “Safe”, which would render an object
invulnerable, was left on the cutting room

floor because it was hazy, and uninteresting.

Not everything that made it into the game is a
complete winner, if you ask me:

a stage where you trap Keke

under words and then push them away from the
corner is awkward and confusing, and the word

“Swap” is like “Tele” but not as cool.

With 200-odd stages, though, there’s always
going to be a few that don’t click for everyone.

But Teikari points to an army of playtesters
who gave feedback on stages, and discovered

alternative solutions..

“I’m extremely thankful for how much testers
have done for the game”, he says.

That group of testers, it turns out, is a
who’s-who of puzzle game wizards, and includes

the designers behind Ending, A Good Snowman
is Hard to Build, Pipe Push Paradise, Starseed

Pilgrim, Minit, and The Witness.

Baba Is You is a surprising, silly, and mind-bogglingly
complex game.

And it had every chance of becoming too difficult
to grasp, too esoteric to understand, or too

freeform to actually produce good puzzles.

But Arvi Teikari has proven himself as a master
of puzzle design.

He introduces the loopy logic of Baba Is You
slowly and subtly, so everyone can understand it.

With his reverse-engineering process, he buries
a clever trick under layers of problems.

But they’re never red herrings or pointless
busy work - they’re about leading the player

to the catch at the centre of the puzzle.

And he’s more interested in surprises and
silliness than rock-hard challenge, making

for a game that will make you laugh more than
it will make you frustrated.

It’s simply a really great puzzle game,
built on a fresh concept that was executed

perfectly.

A no-brainer for this year’s final video.

Hey, thank you so much for watching!

I just wanted to take a moment to say thanks for
all of your support in 2019.

I’m really proud of the stuff I made and
your support has meant the world.

I’ve already got so many video ideas lined
up for 2020 but it's time for a quick break.

So I hope you'll have an amazing Christmas, and
I’ll see you in the new year.